US Bridges

Mo 89 S over Gasconade Rvr

Fair

Osage County, Missouri · S 16 T 42 N R 8 W · Structure no. 1172

Built
1964
61 years old, rebuilt 2023
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
793 ft
4 main spans
Daily traffic
2,822
2024 count
Owner
State
State Highway Agency

About this bridge

Mo 89 S over Gasconade Rvr is a steel continuous stringer/multi-beam or girder carrying Mo 89 S over Gasconade Rvr in Osage County, Missouri. It was built in 1964 and reconstructed in 2023, so it is 61 years old, older than the Missouri average of 45.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 2,822 vehicles a day, roughly 9% of them trucks, projected to reach 4,939 by 2044. The structure is 793 ft (241.7 m) long and 31 ft wide. If it were closed, the detour would be 49.7 mi (80 km).

Location

Open in Google Maps
CarriesMo 89 S
CrossesGasconade Rvr
LocationS 16 T 42 N R 8 W
RouteState Highway 89
CountyOsage County
StateMissouri
Coordinates38.38883, -91.82031
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34.7 US tons
Inventory rating20.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4 (+3 approach)
Design loadH 15
Structure length793 ft (241.7 m)
Longest span160 ft (48.8 m)
Deck width31 ft (9.3 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,822 (2024)
Projected traffic4,939 by 2044
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed49.7 mi (80 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Mo 89 S over Gasconade Rvr built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 2023.

What condition is Mo 89 S over Gasconade Rvr in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in October 2024.

How much traffic does Mo 89 S over Gasconade Rvr carry?

About 2,822 vehicles per day (2024 count), of which roughly 9% are trucks.

How long is Mo 89 S over Gasconade Rvr?

The structure is 793 ft (241.7 m) long with a longest span of 160 ft (48.8 m) and a deck 31 ft wide.

Who owns Mo 89 S over Gasconade Rvr?

It is owned by the State Highway Agency.